Climate Wire | Oil and gas operations in the Gulf of Mexico are releasing more methane than government inventories estimate, according to University of Michigan researchers.
Their study this week Proceedings of the National Academy of Sciences, one of the first agencies to focus primarily on offshore oil and gas emissions, comparing flight observations with data industry reports to the federal government. Researchers have found high methane emissions from shallow water platforms that serve as central hubs for collecting and processing oil and gas, especially in the Gulf.
“This shows how important it is to have direct measurements,” said Eric Court, co-author of the report and associate professor of climate and space sciences and engineering at the University of Michigan. “Without these measurements, we wouldn’t have had an accurate sense of what the climate impact would be from the Gulf.”
Researchers have found that the carbon intensity of Gulf oil and gas production could be twice as high as government estimates. The calculations included major on-site greenhouse gas emissions, carbon dioxide from combustion, and methane losses from venting.
Although carbon dioxide emissions were fairly close to stock data, the study found that methane emissions from the central hub in shallow waters were higher than those reported, and that the greenhouse effect from federal offshore oil and gas production in the Gulf was higher than reported. Cold vents, where unignited methane is released into the atmosphere, and older facilities close to the coast are the main causes of the underestimation, researchers say. says.
“Methane accounts for the majority of greenhouse gas emissions in the watershed,” says Alan Gorchov Negron, lead author of the report and a PhD candidate at the University of Michigan. “From the literature, people [the] Unlike carbon densities in other fossil fuel basins, methane does not always make up the largest portion of the budget. ”
According to Gorchov Negron, the carbon intensity of offshore oil and gas operations in shallow state waters was about the same as that of consumers consuming natural gas for energy.
Gorchov Negron said there are 160 central hubs in federal shoals and 93 central hubs in state shoals. The analysis does not include emissions from more than 1,700 shallow water “satellite” facilities, some Texas shallow water facilities that do not follow the central hub design, and pipeline leaks. Researchers say these emissions “could be significant,” but they are estimated to be small compared to the central hub.
Such hub facilities tend to be older, which may be partly responsible for the cold air draft, researchers say. The study proposes updating the infrastructure and replacing the venting method with “efficient” flaring that burns natural gas.
Brenda Ekwerzel, climate science director for the nonprofit Coalition of Concerned Scientists, called the reported underestimation of methane emissions “disturbing.” But the study also provides a blueprint for addressing the problem, she said.
“It is encouraging to identify the types of facilities that tend to have this pattern of higher-than-usually-reported emissions,” Ekwerzel said in an interview. “It means that these emissions can be improved and reduced because they appear to be in specific facilities doing specific activities.”
Eric Milito, president of the National Association of Marine Industries, said Gulf oil production is less carbon-intensive than the global average. Most production (92%) comes from deepwater federal facilities, where operators follow strict regulations on flaring and venting, he said.
But he also highlighted research data on emissions from central hub facilities.
“Here’s some additional data that’s important when looking at what they’re finding for some of these central hub facilities. [We] We always want to make sure it is feasible to take steps to reduce emissions,” Milito said. “And that will be the important data.”
The researchers said they hope the EPA and the Office of Marine Energy Management will employ their measurements when making future decisions about oil and gas leasing and production.
Chris Eaton, senior attorney for EarthJustice’s Oceans program, said the study has potential implications for the Biden administration’s five-year offshore oil drilling plan, which is due to be announced in December.green wire, March 8).
If the administration bases its plans on inaccurate measurements of methane emissions, it could inaccurately assess the climate impacts of further drilling in the Gulf of Mexico, he said.
“We shouldn’t be doing any more leasing,” Eaton said. “If they can’t control this, it will only add to the methane problem.”
This story also appeared energy wire.
Reprinted from E&E News with permission of POLITICO, LLC. Copyright 2023. E&E News provides essential news for energy and environmental professionals.
